This invention concerns an electromagnetic relay having a base plate through which a plurality of terminal tongues extend, with one of the terminal tongues being a normally-open contact tongue supporting a normally-open contact, with the normally-open contact tongue having a substantially L-shaped bend therein.
Particularly in modern motor vehicles which have a multiplicity of electronic apparatus, among other electrical components, many relays are employed. In this regard, small-size relays, so-called microrelays, which need very little mounting space and which, therefore, lend themselves particularly well to being integrated into complex electronic circuits, are increasingly preferred.
Naturally, when microrelays are employed, reliable operation and long life are demanded. At the same time, production costs of such relays should remain low. These requirements cause the following problems during manufacture of microrelays:
With the manufacture of large-size, or large structure, relays, generally manufacturing processes are preferred in which an adjustment of assembled relay components can be avoided because process steps necessary for such adjustments represent a substantial cost factor.
Particularly small-structure relays demand, contrary to large relays, a particularly exact fabrication method. Individual relay components can, therefore, because of their small sizes, have only small manufacturing tolerances so that the manufacture of such microrelays is disproportionately expensive. Experience has shown that it is more convenient, when manufacturing such microrelays, to allow larger manufacturing tolerances during manufacture of individual relay components and then to carry out adjustments when the components are assembled, that is, particularly adjusting the positions of the components relative to one another.
This method proves to be particularly cost-effective if the adjustments can be fully automatic during relay assembly.
To accomplish this it is necessary to design relays to be assembled so that components thereof can be mounted in a particularly uncomplicated and cost-effective manner and so that, preferably, during the mounting, simple, cost-effective, and fully automatic adjustments, particularly of spaces between relay components, are possible.
An important distance or space for the proper function of a relay is represented by a contact space between a normally-open contact and a movable switch contact arranged on a switch contact spring for a relay that has not been activated.
An electromagnetic relay is known from German Offenlegungsschrift DE-OS 34 23 271 in which an L-shaped beam on a coil frame forms a measuring level. For adjustment of a normally-open contact, this known relay is first placed on a measuring device. Thereafter, by means of a sensing device, various spacings between relay components and the reference level are determined. In a further step, by using these measured spacings, the normally-open contact of the relay is adjusted.
This known relay is thereby constructed in a relatively expensive manner. Also, the measuring and adjusting procedure is relatively complex, since it is carried out by a plurality of series process steps.
A relay with a base plate is already known from German Offenlegungsschrift OS-DE 27 05 961 in which L-shaped fixed contacts are held and with their free ends supported.
It is disadvantageous that the supports are at fixed engagement points with relay components, in particular with an electromagnetic coil frame. Because of this, an exactness of contact spacing is, in turn, dependent upon tolerances of relay components which, as already explained, particularly for microrelays, causes problems. A later adjustment of contact spacing is not provided here.
It is therefore an object of this invention to provide a particularly uncomplicated constructed relay for which an adjustment of contact spacing between switching and normally-open contacts, which adjustment is particularly uncomplicated, cost-effective, and fully automatic, is possible.